THE Family Planning Association sperm bank has broken two records by having the highest number of donors and the lowest insemination rate at the same time. In the first seven months of this year, 109 donors visited the association; in the previous 10 years no more than 100 donors showed up per year. Statistics also show that only 36 inseminations were made this year, compared with the second lowest record of 60 last year. The association's executive director, Dr Margaret Kwan Shuk-wa, said the figures reflected a high failure rate in sperm tests. ''Ninety per cent of donors failed our physical examination. We found troubled semen, having low density or containing white blood cells. In some cases, we found protein in urine and some donors had high blood pressure,'' Dr Kwan said. She believed that fewer than 10 per cent would reach a second test, which shows whether donors are infected with HIV. Most of the 109 donors were white-collar workers aged below 30, although the association had launched a campaign at universities and colleges earlier this year. Donors have to be Chinese, between 18 and 45 years old, physically fit, heterosexual, [** see clarification 31-8-94 donors do not have to be heterosexual **] and never to have lived in an area where AIDS is prevalent. They have to sign an agreement not to seek information about the recipients or their children. The sperm bank is considering increasing the $300 ''travelling expenses'' it pays donors. ''We don't like the idea of using money to attract donors. We would like to appeal to their good intentions. But we may take advice from the public and review the fee,'' Dr Kwan said. In the past 10 years, 108 recipients have been made pregnant.